On Tue 2019-01-15T10:50:10-0800 Tom Van Baak hath writ: > Nope. All minutes have 60 seconds in Excel. And in Windows. And > in Unix/POSIX. Really any computer system that uses a fixed "epoch" > and a ticking "counter" is ruined by leap seconds. The systems differ > in their epoch's, they all differ in their counters, they can all be > set to UTC, except they all fail when there's a positive or negative > leap second.
Nowhere did the folks who were there at the inception of leap seconds say so explicitly, but from reading how things worked over the history of the time services and what the folks paid to provide those services wrote, I am reasonably sure that they also believed that all minutes consisted of 60 seconds, and all days consisted of 86400 seconds. I believe that the concept in their heads was that occasionally there are two calendar days which are not adjacent by one SI second. Or, if the earth rotation were to speed up enough, there might be two calendar days which overlap by one SI second. The notation 23:59:60 is merely a tag for conveniently indicating when a second was inserted between two calendar days. The clock is disconnected from the calendar. Understandably this notion should trigger objections that it is technically barren. At this point I would answer "Yes, and they knew that." They were being paid by their governments to provide the legal and operational time of their nations. Their job had always been to tell the people of their country how to set their clocks. So when a senator or cabinet official asked "Can you tell me what time it is?" they had learned over the course of their careers that the answer was not to wander off into a long technical discussion about how sausage was made, but to smile and say "Yes." Similarly for the 1970 CCIR decision about leap seconds: when facing a chamber full of folks at an international assembly that had the power to dictate how every member nation should set their clocks in the same way that was consistent with the laws of all those nations, the answer was to smile and say "Yes, everyone has agreed that this is the best way to do it." Their job was not to say that the technical folks who made that decision had already decided to disregard that in the systems that they controlled, broadcast navigational signals based on TAI, and make almanacs based on UT (not UTC). -- Steve Allen <s...@ucolick.org> WGS-84 (GPS) UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855 1156 High Street Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 https://www.ucolick.org/~sla/ Hgt +250 m _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com https://pairlist6.pair.net/mailman/listinfo/leapsecs